1. Field of the Invention
The present invention relates to a selective calling receiver and, more particularly, to a selective calling receiver which allows a user to grasp the degree of emergency of a call with only the auditory sense and a method of switching the alert operation of the receiver.
2. Description of the Prior Art
Radio selective calling receivers are currently widely used as media for providing messages addressed to persons and information messages (e.g., stock prices).
The user of a radio selective calling receiver (selective calling receiver) is notified of reception of an incoming message addressed to the person by a alert means such as sound generation by a loudspeaker or vibration by a vibrator. The user recognizes the reception and then externally operates the receiver to stop the alert operation.
As a known technique associated with the present invention, Japanese Patent No. 2643619 discloses a technique associated with a radio selective calling receiver having an auto-reset function.
FIG. 1 is a block diagram of this radio selective calling receiver. A radio signal received by an antenna 201 is amplified and demodulated by a radio section 202. The demodulated radio signal is shaped by a waveform generation circuit 203 into a waveform that can be read by a decoder 204, and output as a shaped radio signal.
A quartz oscillator 205 generates a reference clock. The shaped radio signal is synchronized with the generated reference clock. The decoder 204 compares an ID number contained in the synchronized radio signal with its own ID number stored in a memory section 206.
When it is determined by comparison that the two numbers match, the quartz oscillator 205 notifies an alert function control section 207 of it. The alert function control section 207 is connected to an auto-reset timer 208, mode change-over switch 209, reset switch 210, and auto-reset setting switch 211.
The auto-reset timer 208 counts a predetermined time. The mode change-over switch 209 switches between the auto-reset state and manual reset state of the alert function. The reset switch 210 performs manual reset. The auto-reset setting switch 211 selects one of the alert functions related to reception, i.e., sound generation, vibration, and light emission, which is automatically reset in setting manual reset, and sets the function.
The alert function control section 207 notifies the user of an incoming call in response to an alert from the decoder 204. As the alert means, one of a loudspeaker 213, LCD 215, vibration generation element 217, and light-emitting element 218 is set in advance.
Even when the various alert functions are switched to the manual reset state, this radio selective calling receiver automatically resets the alert function set by the auto-reset setting switch after the elapse of a predetermined time counted by the timer.
This radio selective calling receiver can prevent any wasteful current consumption. This receiver also alerts based on setting for continuously generating sound or based on setting for automatically resetting sound generation in accordance with the degree of emergency of a call.
However, the user cannot discriminate the sound pattern of alert based on setting for continuously generating sound from that of alert based on setting for automatically resetting sound generation. For this reason, the user must grasp the degree of emergency by confirming the displayed contents.
A demand has arisen for a selective calling receiver which allows the user to discriminate the sound pattern based on setting for continuous sound generation from that based on setting for automatically resetting sound generation and grasp the degree of emergency of a call.